THE CASE
A 28-year-old G1P1 initially presented to the family medicine clinic 4 weeks postpartum to discuss possibilities for contraception. She had received her prenatal care through a midwife and had had a successful home delivery. She was exclusively breastfeeding her infant daughter but wanted to ensure adequate spacing between her pregnancies.
During the discussion of possible options, the patient revealed that she had previously had an intrauterine device (IUD) placed and expressed interest in using this method again. A levonorgestrel-releasing IUD (Mirena) was placed at 6 weeks postpartum, after a negative pregnancy test was obtained.
The patient returned to the clinic about 6 months later with complaints of increased difficulty maintaining her milk supply.
THE DIAGNOSIS
The patient had taken a home pregnancy test, which was positive—a finding confirmed in clinic via a urine pregnancy test.
Gestational age. Since the patient had an IUD in place and had been exclusively breastfeeding, gestational age was difficult to determine. A quantitative human chorionic gonadotropin (hCG) test showed an hCG level of 12,469 U/L, consistent with a 4-to-8-week pregnancy. An ultrasound performed the next day showed a single intrauterine pregnancy at 21 weeks.
IUD location. There was also the question of the location of the IUD and whether it would interfere with the patient’s ability to maintain the pregnancy. On ultrasound, the IUD was noted within the cervix and myometrium. After discussion of the risks, the patient chose to leave it in place.
DISCUSSION
IUDs are among the most effective forms of contraception; levonorgestrel-releasing IUDs are more effective than copper IUDs.1 The rates of failure in the first year of use are 0.8% and 0.2% for copper and levonorgestrel-releasing IUDs, respectively.1
Continue to: The Lactational Amenorrhea Method